Missing ability to format a date to a String

[sethladd]

Building an app that needs to display dates. Would be really nice to have built-in support for formatting dates into Strings, configurable with a variety of patterns.

[sethladd]

cc @floitschG.

[floitschG]

This is probably something we want to tackle together with i18n.

[sethladd]

cc @efortuna.

[sethladd]

Added Library-i18n label.

[efortuna]

Set owner to @efortuna.

[efortuna]

Transferring this bug to Alan, who's been actually implementing date formatting. We've got date formatting in the i18n library. I think the question is should we do something further for overall date formatting outside of i18n for M1?

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Set owner to @alan-knight.
Added this to the M1 milestone.

[alan-knight]

I think that what we've done for i18n formatting seems adequate for M1 for general formatting. Seth can disagree if he wants. Current basic usage now (or as soon as the CL for async initialization goes in) is
#import('package:intl/date_format.dart');
#import('package:intl/date_symbol_data_local.dart');

initializeDateFormatting('en_US',null).then( (_) {
  var f = new DateFormat.yMd().Hms();
  print(f.format(new Date.now()));
);

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cc @sethladd.
Added Fixed label.